Punching apparatus for sheet or strip material



Dec. 29, 1953 R. H. E. SCHLECHT PUNCHING APPARATUS FOR SHEET OR STRIP MATERIAL Filed April 20, 1949 ATTORNEY Dec. 29. 1953 R. H. E. SCHLECHT 2,664,161

PUNCHING APPARATUS FOR SHEET OR STRIP MATERIAL Flled Aprll 20 1949 2 Sheets-Sheet 2 INVENTOR RoaERT H. E. SCHLECHT ATTORNEY Patented Dec. 29, 1953 UNITED STATES A,PATENT OFFICE PUNCHNG APPARATUSFOR SHEET OR STRIP MATERIAL Robert Schlecht, Aiton, M0. Application April 20, 1949, Serial No. 88,669

17 Claims. (Cl. 164-895) fective and positive operation, for punching or perforating paper, leather, cloth and other ymaterials including relatively soft metals and the like, which are suitable to punching operations.

ln general, it is the purpose oi the present invention to aiiord a highly compact and readily portable punch device of electromagnetically operated, impact drive character for automatic punching of materials, wherein the device enibodies control provisions of novel character certain of which are under direct regulatory control of the operator.

In line with the foregoing general statement, it is an important object of the present invention4 to provide an automatic punch device of a novel and highly effective character, vlfhich is operable selectively, for producing in materials i the character indicated, punchings or perforations of regular or irregular spacing and in any predetermined or desired design or pattern.

Another important object of the invention is to provide a readily portable punch device of novel and compact construction, which is adapted for multiple punching automatically in respense to step-by-step or walking advance of the device in any direction over the surface of the material to be punched.

A futrher object is to provide an automatic punch device in which the displacement speed and force of the punching element in punching operation, are controllable Within relatively wide limits, whereby the device may be regulated for periorating materials difering in thickness and resistance to punching.

A further object is to provide an automatic punch device which is fully operable to produce complete and clean-cut perforations in materi-v als of the character indicated, and which is capable of producing indentations or imprintsin surfaces of metallic or non-metallic materials, where imprint-ing rather than periorating is desired, as for example, in center-punching or marking preparatory to drilling or material cutting operations.

Yet another Objectis to provide a punch device having a reciprocable punch member. and embodying electro-magnetically operated means for reciprocating the member in material punching operation, wherein said means produces punching displacements of the member bysimpact action relative to the member,wherebyto'A vassure positive imprinting or clean-cut perforating of the material under punch.

Still another object is to provide an automatic punch device having a reciprocal punch member capable of movement angularly relative to its axis of recip-rocation, wherein angular movement of the member is produced by advance of the device while the member is still in contact with the material punched following the punching stroke, and such angular movement initiates i repeated at each advance of the device over the surface of the material undergoing perforation thereby.

A still further object is to provide an automatic punch device operable cyclically as indicated in the foregoing object, which includes a control provision regulatable for determining initiation of the cyclic operation in response to angular movement of the punch member to a greater or lesser extent, whereby the spacing of successive perforations produced by cyclic operation of the device, may be determined as desired.

The foregoing objects and numerous other objects and advantagesA of the present invention, will appear from the following description of a presently preferred embodiment thereof as illustrated in the accompanying drawing, wherein:

Fig. 1 illustrates in vertical sectional elevation, the present novel punch device;

Fig. 2 is an enlarged, fragmentary section of the device, as viewed'from line 2-2 in Fig. 1;

` Fig. 3 illustrates in front elevation, the control Yswitch assembly of the device;

Fig. 4 is a fragmentary sectional view similar to that of Fig. 2, but showing the punch member in an angularly displaced position;

Fig. 5 is an enlarged view in perspective, of the lower portion of the device shown in association with material to be punched, illustrating a holddown provision for retaining the material against lifting with the punch upon retraction of the latter;

ig. 6 is. an enlarged, fragmentary section transversely of the device in the zone of the magnetic hammer, as viewed from line 6-6 in Fig. 1;

Fig. '7 is a circuit diagram of the electrical portion of the device;

Fig. 8 is an enlarged detail view partly in section, of a tip element for the punch member, the element here shown differing from the form of perforating tip element as shown in Fig. 1, in

that it is adapted for material imprinting or indenting, as for marking drill centers, material cutting lines, and the like, and

Fig. 9 is a sectional View of a switch control expedient, as viewed from line 9-9 in Fig. 3.

Referring to the drawing by suitable reference "characters, the present novel punch device includes a frame which conveniently to the compactness of the structure, is constituted by a tubular member le, preferably a single tube of a suitable rigid, non-magnetic material, as brass or the like. Arranged longitudinally in the tube it is a rod member Il of suitable non-magnetic material, as stainless steel or the like, which is reciprocably displaceable in punch operation, as will hereinafter appear. The upper end l2 of the rod is supported and guided in rod displacement, by a plug element I4 seated in the upper end l5 of tube iii, the plug having tube vent openings !5. Plug ld is retained in adjusted position longitudinally relative to the tube end, by a splitcollar i@ embracing the plug in clamped relation thereto, and supported on the tube end l5 as through the collar extension I9 threaded or otherwise connected to the latter. The rod is threaded over its end portion l2, and threaded thereon is a stop member 2B providing a shoulder 2| forming a spring mounting seat for a buier spring 22, and presenting additionally, an annular nange 23. A lock-nut 2e retains the stop in position on the rod. Buffer spring 22 which serves a purpose recess or socket 2 therein, this spring serving constantly to load the rod in the downward direction of its displacement. A larger, buffer spring 28 carried by the plug lil, has its free end disposed for engagement by the stop ange 23 in the course of upward movement of the rod, the spring when so engaged and compressed, serving thereby to stop further rod displacement in the upward direction, and at the same time, imposing on the rod a force in aid of the downward stroke of the latter.

The lower end of rod i l is suitably rigidly connected to the upper end of a rod element 30 preferably formed of a hard material such as stainless or tool steel. IThe rod is enlarged at its upper end, to afford an abutment 3l presenting a top annular surface 32 constituting a striking face or anvil for a punch actuating hammer presently to be described. Rod 30 in its lower end portion,

provides a shoulder 34 and a threaded end 35, the

shoulder serving several purposes one of which is as a lower guide for the connected rods l l and 30 in reciprocal movement. Suitably fixed within the lower end portion 36 of frame tube l0, is a tubular element 38, and slidably engaged in element 38 is the shoulder 34, the tube element and shoulder thus cooperating to provide both lateral support and displacement guiding support for the connected rods.

Carried by the rod element 30 in extension below its lower end portion, is a punch rod or stem 39 which projects in exposed position below the lower end t@ of frame tube l0, the stem normally supporting on its lower end 42, a punch or material perforating tip element 33 of a character t be described later. The upper or head end of the punch stem 33 is formed to provide a frustoconical enlargement or head l with the larger end uppermost, and such end is yieldably retained in engagement with the bottom face of the threaded end 35 of rod 36, by a compression spring 46 having its upper end bearing against the conical surface of head te near the larger end thereof, and its lower end bearing against a cap 41 threaded on the rod end 35. Cap il is apertured as shown, to accommodate the punch stem in extension therethrough and to permit angular movements of the stem relative to the cap, as for a purpose to appear.

In the presently preferred embodiment of the invention, the movable or reciprocal punch member considered as a unit comprising the rods H, 36 and stem 39, is actuated by electro-magnetic means including a plunger or armature 5@ in the form of a tubular element of magnetic material which is freely slidably received in frame tube l0. At its upper end is a disc 5l centrally apertured to accommodate rod il, the disc being of hardened steel to serve as a hammer head for engagement with the yieldable abutment or buier spring 22. A similar hammer disc 52 is carried by the lower end of plunger 5S, for striking engagement with face 32 of the rod anvil or abutment 3l.

Externally on the tube l@ are electro-magnet coil units till and 55 in relative adjacence, the upper coil unit te when energized, eiiecting magnetic attraction of plunger 5t to cause the latter to rise in tube le and tend to assume a magnetically centered position relative to the coil unit. The plunger as thus displaced, engages the buffer spring 22 by impact of its hammer head 5l thereagainst, compressing the spring and producing a sudden and rapid elevating displacement of the rod assembly including the punch stem 3Q. Upward displacement of the rod assembly is arrested by the buffer spring 2t as hereinbefore indicated. O-n the other hand, energization of the lower coil unit 55 attracts plunger 5c, causing downward movement thereof in tube it toward a magnetically centered position relative to the coil unit. In so moving, the lower hammer head 52 impacts against the face 32 of the striking abutment 3l, and thereby produces a sudden and rapid downstroke of the rod assembly. The plunger-effected downstroke or punching stroke is aided in initial displacement, by expansion of the buffer spring 28 against the rod stop ange 23, and thereafter to a lesser degree by expansion of the spring 26, while the electromagnetically produced downstroke of the hammer is aided by expansion of the bufer spring 22, as this will be now appreciated.

Before turning to the control provisions for determining and regulating punch operation, it is desired here to describe the mounting arrangement of the assembly. The punch device according to the present embodiment, is of a portable character and adapted for manual displacement of the punch device as a whole, in walking manner over the surface of the material to be punched. To this end, there is provided a base ring 5B preferably of the form shown by Figs. l and 5, on one side of which is secured an upstanding bracket 58, the bracket having a handle 59 attached thereto as by the headed bolt et. Projecting from the bracket and centrally over the base ring 56, is a member 62 affording a split-collar 53 to receive the lower end of frame tube It in clamped, sup- Sporting relation thereto. lThrough the splitcollar, the tube l may be adjusted vertically relative to the base ring.,56. In application, the base ring` is rested vdirectly upon the exposed surface of the material to be punched, such material being spread upon a suitablesupporting surface, as the top of a work benchor the like. The punch stem 39 and `its punching tip 43 thus are located over the portion of the material in the center of the base ring. Included-in the base assembly is a tensioning spring 64 (Figs. 1 and 5) arranged to have its coil portion 66 positioned for rest under tension,vagainst the materialunder punch in the area thereof underlying the punch tipl 43, as illustrated more particularly in Fig. 5. vThe spring not only holds the indicated area of the material in place for punching, but` effectively prevents lifting thereof with the punch tip 43 upon retraction of tliepunch following .the perforating operar tion.

The electrical circuit controls for the coil units 54 andv 55 are carriedon a panel block here comprised of a brass plate 10 and a face plate 1| of insulating material, secured thereto, the block being mounted directly on the lower end of tube I0 (Fig. 3) by attachment screws 12. On the panel is a main switch comprising opposed stationary contacts 14 and 15 carried on insulating brackets 16 and 18 respectively, suitably attached to the panel. The-contact 15 which is adjustable for varying the relative spacing of the opposed contacts, has associated therewith a movable contact 19 on a resilient arm 80 of conducting material. Arm -80 is supported on a movableinsulating arm 82, the latter having a hub 83 secured to onekend of a shaft or pin element 84 which is rotatably journalled through the lower right hand corner section of the panel (Fig. 3, and also shown in part in Fig. l). Also on arm -82 is a conductor arm 86 on the end of which is a contact 81 opposed to and cooperable with the xed contact 14. On thepanel near arm 82 is a circuit connector post 88 'between which and the movable contact arms 80 and86, is a flexible lead Pivoted on a stud 9| xed to the panel, is an insulating arm 92 which supports at its free end an L-shaped cam element 94 of conducting material, having thereon a contact 95 forming part of a control switch. A nger actuator 96 is pivoted on a stud 98 xed to the panel, and includes a cam face |00 adapted for engagement with the L-shaped cam element 94, the latter being yieldably biased toward cam face |00 by a curved leaf spring |02 of conducting material, fixed to a conductor arm |03insulatingly carried on a stud |04 on the panel adjacent the contact bracket 16. Circuit connection between contact 14 on bracket 16 and the spring arm |03 is made preferably by a conductor element |09 fixed to contact 14 and bearing in tension, against the hub portion of arm |03.

A spring contact arm |01 having a contact |08 for cooperation with contact 95, is carried by a member ||0 pivoted to stud 9|, the contact arm |01 being connected by a exible or spring-type lead to a circuit-connector post ||2 on the panel. Carried by member ||0 therebelow, is a block I4 of insulating material, provided with a recessed slot ||5 to receive the head end portion 0f a screw ||6 serving a purpose presently to appear. The finger piece 96 has a projection I8 underlying the block 4, operable upon fingerdepression of the actuator tol abut the block and raise the same. -v-'Elevation of the block raises the contact |08 toward contact 95, the latter then being in a position determined by engagement of the cam 94 with an adjustable stop 99. Such depression of thenger piece thus effects engagement of the contacts, which initiates punch operation as will hereinafter appear.

VAs shown by Figs.v Band 9, the stop 99 comprises-a block preferably of inverted U-shape, formed of fiber or other suitable insulating material rand adjustably positioned on the panel face by the stud 98, the latter extending between the legs of the U-shaped block. A shoulder-forming flange 93 carried by or lformed integrally of the stud 98,-serves to clamp the stop 99 in adjusted position on the panel suchthat its upper rounded end 91 is disposed for engagement by the L-cam 94 when the finger piece 96 is in a neutral position, or `depressed as hereinabove described. Moreover, the flange 93 provides a friction seat for the pivotal finger piece196, the latter being urged thereagainst under the tension of a suitable spring such as the spring washer |0| engaged beneath the head of a screw element |05 threaded into the end of stud 98 as shown in Fig.v 9. By present preference, the .stud 98 is threaded through the panel and is held by a lock nut |09.

The neutral position of the finger piece 96 as Y above referred to, is that kin which the cam surface |00 of the piece is clear of the L-cam 94 such as to permit the latter to engage upon the end 91 of stop 99, while the projection ||8 of the piece is near to but out of contact with, the block |24. When the partsare so disposed, the contacts and |08 vwill be separated by a relatively small gap. Moreover, such contact separation in the neutral condition of the control, may be increased or decreased by adjusting the position of stop 99.

Returning to the main switch at the right hand side of the panel, the shaft or pin 84 extends through and outwardly beyond the rear of the panel, and has secured thereon an adjustably extensible lever |9 which has its end |20 turned for projection through an opening |22 provided through the side of frame tube |0 and the upper end section of the Vtubular member 38 (Fig. 1).

.The terminal portion of lever end |20 is rounded as shown, for cooperation with a switch actuator |23 slidable in the bore of member 38, actuator |23 having a slot |24 to receive the lever terminal portion, as illustrated inF-g. 1. The upper end of the actuator is formed .to provide a ange head |26 which in the lowered position of the actuator, rests upon the upper end of the member 38 (Fig. 2). Upward displacement of the actuator is limited by` a finger element |21 extending inwardly from a bracket |28 removably secured externally on the tu'be I0 by screws |30, the finger projecting into a slot |3| in the side of the actuator substantially opposite the slot |24. When the punch rod assembly is lowered or at the end of itspunch stroke, as shown in Fig. l, the actuator is lowered to admit the lever terminal in the slot |24, the lever being loaded in the direction to insert its terminal in the slot, by a suitable means such as the tension leaf spring |32 arranged between the lever and an abutment 34 preferably projecting from the rear side of the panel block. In such position of the lever, the movable contact 81`of the main switch will be in engagementwith fixed contact 14.

Now upon upward or punch retracting displacez;,lent of the punch rodAV assembly, the shoulder 34 of rod element 30 engages the lower end of the actuator |23, elevating the same with the punch rod assembly,V and thereby effecting through lever engagement by the lower inclined cam end |35 of actuator slot |24, pivotal displacement of the lever in the clockwise direction as viewed in Fig. l. The'lever when so moved, opens the contacts 14-81 and engages the movable contact 19 with the fixed contact 15, and at the same time, the lever terminal end bears against the` side of actuator |23 below the slot |24, and thereby tends to maintain the elevated position of the actuator in consequence of lever` tensioning by spring |32. Accordingly, in order to assure return of the actuator upon the downstroke or punching stroke of the rod assembly, there is here included in the rod assembly, means for effecting actuator return. Sleeved on the rod and within the plunger U, is a non-magnetic member |36 which may be here termed a trigger plunger, the same being formed at its lower end to provide a plurality of forwardly extending lingers |38 which project through openings |39 (Fig. 6) in the bottom hammer disc 52 of the armature plunger (Figs. l and 6). The trigger plunger is capable of limited axial movements relative to the armature, being confined by the armature discs 5| and 52 such that it follows armature displacements without retraction of the fingers |38 from the disc openings |39. The trigger action of the member |33 occurs at the end of the punching stroke of the rod assembly when downward movement of the armature 53 stops. As such time, the trigger plunger continues downwardly in the armature in consequence of its downward movement, to extend its fingers |33 through disc openings |33 and bring them into striking abutment with the head flange |26 of the actuator |23. The actuator in reaction to such impact, is thereby forced downwardly until the terminal end of the switch operating lever ||9 again enters the actuator slot |24, and thereby opens contacts 'I5-19 and closes contacts 'I4- 81.

Fig. 1 illustrates the circuit arrangement of the coil units and control switches as now described. As there appears, a lead |59 from one end of the upper coil unit 54, and a lead |5| from one end of the lower coil unit 55, are joined in connection to one side |52 of a supply line leading from a suitable electric power source (not shown) which may be 110 volt, 60 cycle mains. The other end of the lower coil unit 55 is connected by a lead 54 to a control resister unit or rheostat |55, the rheostat in turn having a connection by lead |56 to the contact 15 of the main switch. Extending from the opposite side of the upper coil 54 is a lead |58 which is connected to the contact |08 of the control switch, through the switch connector post I l2. The other contact95 of the control switch is connected to main switch contact 14 in the manner already described, as through spring |92, arm |93 and element |06, the latter connection being indicated in Fig. 7 by the reference numeral |51. The opposite side |59 of the supply line, is connected to the post 88 which is in circuit with contacts 19 and 81 through lead 96 and the switch arms 69 and 86, as before described. Preferably, a condenser |69 is arranged across each of the main switch contact sets 14-81 and 'i5-19, to dampen contactarcing. While the rheostat |55 and the condensers |66 are shown only in the circuit diagram, it is to be understod that in practice, these are mounted on the punch device, as for example,

on a side of the coi1 assembly, whereby to complete the fully portable character of the punch.

Describing now the provision for effecting automatic operation of the device in response to advance or walking of the -device over the material to be punched, the screw i I6 having its head end in the slot ||5 of block H4 attached to the structure carrying the control switch contact |08, is extended together with a spacing sleeve |62 thereon, through the panel block and through a slot |63 in the lower end of frame tube (Figs. 2 and 4). The inner threaded end of screw H6 is threaded into an opening in a wall of a cupshaped member |34. Member |63 is telescoped over the lower reduced end |56 of the guide member 38 xed in the tube, and is loaded downwardly by a spring |51, to engage its bottom wall |68 against the upper face |19 at the larger base end, 0f a frusto-conical element |1i hereinafter referred to for convenience, as the movable cone of the mechanism. The conical face |12 of the movable cone engages the internal conical face |14 of a xed annular cone element |15, the latter 'being secured in the bottom end of the frame tube |5, as by the threaded connection shown. Cone |15 has openings |15 to vent the tube l0 in its lower end portion. In the present example, the angle of the conical faces |12 and |14 is approximately 45 degrees to a diametral plane of the tube l5, whereby to facilitate sliding movement of the movable cone relative to the fixed cone. Movable cone |1| has a central or axial bore |16 of a diameter to accommodate angular movements of the punch stem 39 in extension therethrough, and is formed further, to provide a relatively thin annular ange |18 in the upper end of bore |16, presenting a smoothly rounded margin disposed relatively closely about the stem 39.

When with the parts positioned as shown in Fig. 2, the stem 33 is displaced angularly from the axis of punch displacement, as for example toward and to the limit shown in Fig. 4 wherein the stem abuts the lower margin of the conical face |14 of xed cone 15, the stem engages the rounded margin of flange |18 and urges the cone 11| to one side, causing the cone to slide up one side of the conical face |14 of lowered xed cone |15. Stem 39 rocks on the rounded margin of the nange and because of its angular relation thereto, tends to lift the cone. However, the spring-pressed cup member |64 having its bottom wall |53 in contact with the upper face |10 of the cone, opposes and tends to balance the cone lifting action of the stem such as to relieve the bearing pressure of the upper cone against the lower cone, whereby the upper cone |1| moves smoothly and easily up the side of the lower cone as the stem is angularly displaced.

As the cone |1| is thus elevated, it raises the cup member |64 and the latter, through the screw H6, correspondingly raises the block lili. The resulting elevation of the block il@ brings control switch contact !33 toward the upper companion Contact for engagement therewith to complete the punch actuating circuit controlled by these contacts. The extent of angular movement of stem 39 necessary to produce engagement of the contacts, is determined by the operator through location of the member 96 either in its neutral position wherein cam 34 rests on stop 99, or in an elevated position to engage the cam face |39 with the contact cam element 94 such as to locate the contact 35 in'a position of greater or lesser elevationl relative to the contact |08 9, when the `latter is in itsA initial lowered S position; The foregoingv serves VaZ purposepresently to appear.

When stem'39 is released for return toits normal vertical position, the cone is returned by the springloaded 'cup |54 to its centered position on xed cone |75' (Fig. 2). .As this occurs, the iiange i'liibearing against the stem, serves in conjunction with the spring 46 acting on the'head 44of'the stem 3S, to effect positive return of the stem to'its vertical position. The action is'further facilitated'by the upward displacement of the stem'which is effected at such time, as thisv will appear presently.V

It is desired to emphasize here that with the and the springs including springs 22, 28 and 28, substantially all metallic elements of the punch assembly within the frame tube I or otherwise nearthe effective magnetic elds of the electro magnetic coil units,` are provided of suitable nonrnagnetic material, as stainless steel or the like. This is adhered to in the present structure in order Ato avoid magnetic leakage or dissipation of the magnetic forces which if permitted, would seriously impair or reduce the magnetic power of the device.

DescribingV now the operation of the' present novel punch device, upon placement of the device on the surface of the material to be punched and assuming connection has been made to the electric" powerV source, the operator pivots the finger actuator 95A in the counterclockwise direction as viewed inzFig. 3,' to bring the projection |18 into lifting engagement with block I |4. ward movementof block ||4 thereupon eleva-tes contact |08 towardv contact 95 until'the contacts are'engaged.Y Since the reciprocal'punch mechanism isnormally lowered`in the Lie-energized condition of the' punch device, the parts thereof` will appear asin Fig. l, with the bottom end oi the punch tipelernent 43 resting on the materia to be punched, and with the lever ll9'located as shown, to close contacts T4-81 of the main switch'. Consequently, upon engagement of contacts S35-|08 of the control switch, the energizing' circuit. of the upper coil unit 54 will be completed (Fig. '7), thereby eifecting magnetic attraction of the plunger 50 to effect upward displacement of the punch rod assembly in the4 mannerhereinbefore described.A As this occurs. the resultant elevation of the switch actuator |23 produces outward pivoting of ther lever||9 to cause'openingof 'contacts 'I4-81 and closure of contacts 'i5-19, the lattervv completing thev energizing circuit of the lower coil unit 55. It is to be notedin connection with the-foregoing, that inthe upward magnetic attraction of the plunger' 5B, the'plunger moves rapidly into striking abutment oflits head disc with the buffer spring 22, thereby producing a quick impact lift of the rod assembly which following a punching stroke, ei'ectsa positive retraction of the punch tip 43 from its perforating embedment in the punchedmaterial. Moreover, actuation of the main switch lever Il!! at this time, is delayed such as to permit full retracting displacement of the rod assembly. The delay here is eiected as a result ofthe relative spacing of the rod shoulder '34 and the lower endY of the actuator s |23 which obtains at the end of the punch stroke.

as shown in Fig. 1, since such spacing 'requires that the rod assembly be retracted to an ap-4 preciable extent `before shoulder 34 engages and elevates the actuator |23.

Now vupon energization ofthe lower coil unit 55, the plunger 5|)l is i attracted rapidly downward, causing itslower head disc 52 to strike or effect a hammer-like blow against the face 32 ofthe hardened anvil or abutment element 3| on the rod 3Il' of the' punch rod assembly. Such produces impact displacement of the rod assemblydownwardly in its punching stroke, which thus effects with considerable force, punching or perforating entry of the tip 43 in or through the material under punch. In the punching stroke, the rod or stem 39 is maintained vertical in axial coincidence with the longitudinal axis of the rigidly connected rods and thereabove, through the loading spring 46 acting on the stern head 44 in a' manner yieldably to force its large en'd'face into full contact with the bottom face 'of'the'end portion 35 of rod 30. As so maintained, the stem moves in a straight line toward the material in the punching stroke of the device, whichthus facilitates the attainment of clean-cut perforations. At the end of the punching stroke, the trigger plunger |36 eiects return of the switch actuator |23 in the manner hereinbefore described, and thereby causes actuation of the main switch to open contacts l5- 19 and close'contacts 'I4-81. Whereupcn punch retraction again takes place, with the operation continuing through the cycle described, so longas the iingerpiece 96 is held depressed such as to maintain block ||4 raised and the control contacts S-|08' closed. With the punch operating automatically asindicated, the operator may repeatedly'lift the whole punch device and reedeposit it on the material to be punched, thereby effecting successiveperforations in any desired pattern or'design. It is to be noted here that the operator is aided appreciably in effecting movement of'thepunch device from point to'point over the' material under punch, by the tendency to upward lift of the device as a whole, consequent to upward electromagnetic displacement of the hammer and its impact engagement with the buffer spring 22 in the cycle of punch operation; This latter' effect with its now obvious'advantage in operation of the device, is present whetherthe punch is operatedin the manner hereinabove described, or operated by a walking displacement of the device over the material, as'will be described hereinafter.

While one" or any successive number of perforations may be produced in the manner above noted, the' operator mayy condition the punch deviceso that it will produce successive perforations merely' upon pushing or walking the device overth'e material in any desired or predetermined direction thereover. To such end, thepperator starts the punch in operation as above'described,l andthen pivots the finger piece 96 counterclockwise (Fig. 3) either to its neutral positionv or toa position elevating the contact 95 through raising of the cam element 94V by the cam face |00 on'the finger piece. As this is done, the finger piece projection |8 leaves block ||4, releasing the same to its lowermost position as effected by the spring-loaded cup member |64. The resulting separation of the control contacts E15-|08, stops punch operation with the punch rod assembly at'theend` of its punching stroke, whereinthe tip 43 is embedded'in the underlying material. Now by advancing the punch device such as to slide the base ring along the surface of the material, the stem 39 having its tip 43 embedded inthe material consequent to the'last punching-Stroke; will be caused to move angularly. When so moved, it eifects through the cone cup member |64, screw ||5 and block ||4 actuated thereby in the manner hereinbefore described, an elevation of the con-- tact |09 until the latter engages contact 95. Whereupon, the punch operates to retract the stem 39 from the punched material, with the stem returned to the vertical punching axis in the manner described hereinbefore, and thence to produce a punching stroke. The foregoing automatic action of the punch will be repeated at each advance of the device, so that by walking the punch over the material, successive imprints or perforations will be produced. In the walking'operation of the device. the relative spacing of the perforations or imprints may be determined and varied by regulating the position of the control contact 95 through either the stop 99 or the cam |00 of the finger piece 96, this because the position of contact 95 determines the extent to which the punch stem 39 must be angularly moved in order to bring contact |08 into engagement with the contact 95. For example, if contact 95 is set so that contact |08 engages therewith after angular movement of stem 39 to an extent such that the center-tocenter distance between the tip 43 embedded in the material, and the point of intersection of the vertical axis of punch rods I and 30 with the. underlying material, is approximately a quarter of an inch, then successive perforations will appear at substantially quarter-inch space intervals as the device is walked over the material. It is to be noted here that the adjustable stop 99 is employed to determine or set the initial or minimum gap spacing of the contacts 95-|08, hence to determine corresponding minimum spacing of the perforations or imprints in the material under punch. This initial gap may be Varied of course, by adjusting the position of the stop 39 in the manner hereinbefore noted. Once set to secure the desired contact gap, the punch may be operated with the finger piece 95 in its neutral position, the spacing of the punchings then being uniform and not less than the spacing corresponding to the set gap. On the other hand, materially greater spacing of the punchings are obtainable within relatively wide limits, through actuation of the finger piece 9S to engage its cam surface |00 with L-cam 94 whereby to effect the desired increased separation of the contacts S35-|09. The spacing control in the latter case, is effected at the will of operator and mav be accomplished at any time during the operation of the punch on the ma terial under perforating or imprinting treatment.

As indicated objectively herein, the present punch device is suitable for punching many different materials, as paper, cloth, leather and even soft metals. Because such materials differ widely in their punching resistance characteristics, it is desirable to include in the present de vice means for regulating the force of the punch in its punching stroke. whereby the punching force may be reduced for low-resistant materials where a greater force is not necessary to effect clean-cut perforations, and may be increased in. the presence of more resistant materials, or where several layers of the same or diiferent materials are to be perforated at one time. The control resistor or rheostat |55 in the energizing circuit of the lower or punch stroke producing coil unit 55, as shown in Fig. 7, here serves the foregoing purpose. By adjusting the rheQSlat,

the attractive force of the coil unit may be increased or decreased, with consequent corresponding increase or lessening of the impact force of the plunger 50 against the striking abutment 3| of the punch rod assembly, which thus determines a greater or lesser force of the punch in its material perforating function. It is to be noted also, that the foregoing increases and decreases the speed of plunger displacement pro portionately to the change in magnetic force, which thus affects the ultimate punching force.

It is desired to emphasize here that the present novel punch device is well adapted for and fully capable of producing not only clean-cut perforaf' tions in material of the character herein indicated, but also imprints or indentations in materials suited thereto, including relatively soft metals and the like, such as to mark the materials for subsequent drilling or cutting operations and the like. In either case, the material treatment may extend in any desired or predetermined trend over the material, or in accordance with any line pattern. Accordingly, it is to be understood that unless otherwise expressly stated herein, the terms punch and punching together with references to the punching operation of the device, all as employed herein and in the claims hereunto appended, shall be considered as covering both perforating and indenting or imprinting.

From the foregoing description of the device as illustrated, it will appear now that the present punch device affords a desirably compact and portable unit which may be moved quickly and easily over the material under punch or from one point to another thereon, and from one work table to another as may be desired. While the punch is herein shown and described as a portable unit, nevertheless it will be now appreciated that the unit may be mounted in xed position relative to a work surface, and the material to be treated displaced over the work surface beneath the punch tip, in the punching operation.

An additional feature of the invention resides in the punch tip element 43 as shown in section in Fig. 1 and in perspective elevation in Fig. 5. As therein illustrated, the tip element is detachably mounted on the free end of the punch stem 39, preferably being secured thereto by a through-pin 200. It is formed to provide a socket 20| to receive the stem against a bottom shoulder 202 of the socket, the bottom 202 transmitting the drive force of the stem to the tip in punching operations. Beyond the socket, the element provides a convergently tapered section 204 of hollow form, terminating in a tubular materialentering end 205. In the tapered section 204 are formed wall openings 206 which afford discharge outlets for the portions of the material cored out by the tubular end 205 in material punching. While the tip is held on stem 39 by the pin 200, it may be frictionally seated on the stem, as by affording a split socket wall and contracting the socket into clamped position on the stem.

The tip element 43 as so constructed including the tubular end 205, is thus adapted for the production of uniform, clean-cut perforations in the material under punch. This action of the tip is in consequence not only of its end formation, but importantly herein, of the character of punch operation, which includes the straightline, punching stroke travel of the stern 39 and the magnetic plunger-produced, impact drive of the punch rod assembly in its punching displacement.

13 'While the 'tip`43lof the character'shownand described, may be 'employed yin certain" instances,

in the'application of the vpresent 'punch device' conical end section 208, and a hollow tubular shank section 209 split longitudinally at one side, as at 2|0, the hollow shank presenting abore 2| 2 terminating in a bottom ange or shoulder 2|3 for abutment with the end of the stem 38 in tip application tothe stem. The bore 2|2 of the hollow shank may be of a diameter slightly less thanthe diameter of stem 39, so that in mounting the tip element on the end of the stem, the shank is spread as permitted by vthe split ZID. Spreading. of the shank places the Wall thereof under tension, such as to cause it to contract and hence grip the stem 39 in assembly thereon. To facilitate tip mounting and removal, the tip element is provided with a transverse hole'2l4' through which may be inserted a suitable tool, such as a piece of rod, .by which the tip may be gripped in forcing it onto or from the stern.`

Having now described and illustrated apresently preferred embodiment of my invention, it is to be understood that various modifications may be made thereto Without departing froml the spirit and full intendedl scope of the invention' as defined in the appended claims.

I claim: 1. In al material punching device, an axially movable rod-like punch member including 'a" pact engagement with one abutment, effecting' punching displacement of the member, and electro-magnetically actuated to impact engagement with the other abutment, and meansresponsive to angular movement of said'punch element for effecting electro-magnetic actuation of said hammer for impact engagement 'with-'said' other abutment, wherebyV to effect 'a retracting' displacement of the member.V

2. In a material punching device, a movable punch member adaptedat one endk for material punching, a striking abutment onv theimember.,

a hammer movable in one direction against said strikingr abutment for eiecting' punching-displacement of the member, a stop element including an abutment connected to the member, the' latter said abutment engageable by said'hammer upon movement thereof in an opposite'direction;

for effecting retracting displacement of the mern- C ber, a spring element carried by thesaid stop element and normally extended below the-latter said abutment, whereby the hammeryieldably engages the spring element prior to engaging the said abutment incident to retraction of said member, and means including said spring velement effective on said member in its retracted position, to impose a force thereon in aid of subsequent punching displacement of the member.

3. In a material punchingdevice,` a-movable rod-like'punchV member having relatively spaced abutments thereon and in'cluding'a punch .element at one endl of the member, movable angularly relative to the longitudinal axis of the member, electro-magnetic operating means including a pair of magnet coils and an armature, said armature being movable against one of said abutments in response to energization of one of said magnet Coils, for causing movement of said member and punch element in a material punching direction, energizaton of the other magnet coil causing movement of said armature against the other abutment to produce retracting move ment of the membei'and punch element, and leans responsive to angular movement of said punch element, foreecting energization of said other magnet coii.

4. Ina material punching device, a rod-like punch member includine.- a punch element, movable to and from a punching position, said punch element being movable angularly relative to the longitudinal axis of the member, a magnetic armature for moving said member and punch element, first and second magnet coils in operative relation to said armature, an energizing circuit for said rst coil to energize the same and thereby effect movement of the armature to move said member and punch element tov/ard and into said punching position, an energizing circuit for said second coil, including a control switch therein,

and means responsive to angular movement or 6. In a material punching device, a punch member adapted at one end for material punching,I said member being movable to and from a punching position, relatively spaced abutments on the member, an armature movable between said abutments, a pair of magnet coils in electromagnetic operating relation to said armature, energizing circuit means including a two-position switch, for energizing coils such that in one` position of the switch, one of the coils is energizedA to cause movement of the armature against one of said abutments, to eiTect movement of the punch member to the punching position, while in the other position of the switch, the other coil is energized to cause armature movement against the'other abutment and thereby effect movement of the'punch member from its punching position, and means operable resp-onsively to and in accordance with said movements ci the punch member, for actuating said switch from one to the'vother of its positions.

'7. In a material punching device, aV punch member adapted at one end for material punching', said member being movable to and from a punching position, relatively spacedabutnients on the member, an armature movable between said abutments, a pair of magnet coils in electromagnetic operating relation to said armature, energizing circuit means including a tivo-position switch, for energizing said coils such that in a first position of the switch, one of the coils is 'energized to cause movement of the armature against one of said abutments to effect movement of the punch member to its punching position, while in a second position of the switch, the other coil is energized to cause armature movement against the other abutment, to effect movement of the punch member from its punching position, and control means operable in response to movement of the punch member to its punching position, for electing said second position of the switch, said control means further being operable in response to movement of the punch member from its punching position, for effecting said irst position of the switch.

8. A punching device operable for eiecting successive punching of a material responsively to relative movements of the device and material under punch, the device comprising a punch member including a stem having a punching end, the member being movable to and from a punching position and the stem thereof being capable of movement relative to the remainder of the member, actuating means for said punch member, a two-position control therefor, eiective in one position to cause operation of the actuating means to eiect movement of the punch member to its punching position, means responsive to punch member movement to said punching position, for moving said control to its other position, and control means eiective in response to movement of said stem relative to the remainder of the punchmember as effected by relative movement of the punching device and material while the punching end of the stem is engaged with the material punched, for causing through said control in its other position, operation of said actuating means to eiect movement of the punch member from its punching position.

9. A material punching device operable for eiecting successive punching of a material automatically in response to step-by-step advance of the device over the material, the device Ycomprising a punch member including a stem having a punching end, the member being movable along a rectilinear axis to and from a punching position and the stem being capable of movement angularly relative to said aXis, actuating means for said punch member, a two-position control therefor, effective in one position to cause operation of said actuating means to eiect movement of said member to its punching position, said control in the other position thereof, conditioning said actuating means for operation to eiect movement of the member from its punching position, and control means eiective in response to angular movement of said stem produced by advance of the punching device while the punching end of the stem is engaged in the material punched, for rendering said control effective in said other position thereof, to cause operation of said actuating means to eiect movement of the punch member from its punching position.

10. A material punching device in accordance with claim 9, characterized further by adjustable means for regulating said control means selectively such as to condition the same for response to greater or lesser angular movement of said stem consequent to advance of the punching device while the punching end of the stem is engaged in the material under punch.

11. A material punching device operable for effecting successive punching of a material automatically in response to step-by-step or walking advance of the punch device over the material, the device comprising a punch member including a stem having a punching end, the member being movable along a rectilinear axis to and from a punching position, while the stem isV capable of movement angularly relative to said axis, electromagnetic means including a pair of magnet coils and a plunger operable relative to said punch member for causing movements thereof, an energizing circuit for said electro-magnetic means, including a primary and a secondary control switch, said `primary control switch having first and second control positions, and being effective in the rst control position, for completing the energizing circuit to one coil of said electromagnetic means for causing said plunger to effect movement of said punch member to its punching position, means operated in response to movement of the punch member to its punching position, for actuating said primary switch to its second control position, and control means eiective in response to angular movement of said.

stem produced by advance of the punching device while the punching end of the stem is engaged in the material punched, for operating said secondary control switch to complete the energizing circuit through said primary switch in its second control position, to the other coil of the electro-magnetic means for causing the plunger to effect movement of said punch member from its punching position.

12. A material punching device according to claim 1, wherein the means operated in response to movement of the punch member to its punching position, for actuating said primary switch to its second control position, is operable in response to movement of the punch member from its punching position, for actuating the primary switch to its rst control position.

13. A material punching device in accordance with claim ll, further characterized by meansV for regualting said secondary control switch such as to condition the latter for operation by said control means through response of the latter to greater or lesser angular movement of said stem as produced by advance of the lpunching device while the punching end of the stem is engaged in the material under punch.

14. A material punching device operable for effecting successive punching of a material automatically in response to step-by-step or walking advance of the punch device over the material, the device comprising a punch member including a stem having a punching end, the member being movable along a rectilinear axis to and from a punching position, while the stem is capable of movement angularly relative to said axis, electromagnetic means including a pair of magnet coils and a plunger operable relative to said punch member for causing movements thereof, an energizing circuit for said electro-magnetic means, including a primary and a secondary control switch, said primary control switch having first and second control positions, and being effective in the first control position, for completing the energizing circuit to one coil of said electromagnetic means for causing said plunger to eiect movement of said punch member to its punching position, means operated in response to movement of the punch member to its punching positlon, for actuating said primary switch to its second control position, a xed member having a conical seat, a movable cone member seated on said conical seat and having a portion thereof relatively closely adjacent said stem, and an operating connection between said movable cone member and said secondary control switch, angular movement of said stem consequent to advance of the punching device while the punching end of the stem is engaged in the material under punch, effecting through said cone portion relatively closely adjacent the stem; displacement of the cone member on said seat, the cone member when so displaced, acting through said operating connection to operate said secondary control switch for completing the energizing circuit through said primary control switch in its second control position, to the other coil of the electromagnetic means, whereby to energize the same and cause plunger movement for effecting movement of said punch member from its punching position.

15. A material punching device in accordance with claim 12, wherein said fixed member having' a conical seat and said movable cone member are provided with openings centrally in each, to accommodate said stem in extenison there through, and wherein said portion of the cone member in relatively close adjacence to the stem, is constituted by an annular flange having a rounded margin relatively closely encircling the stern.

16. In a material punching device, a rod-like punch member including a punch element at one end of the member, movable to and from a punching position, said punch element being movable angularly relative to the longitudinal aXis of the member, actuating means including a hammer for moving said member, and control 18 means responsive to angular movement of said punch element for causing operation of said actuating means to effect movement of the punch member from its punching position.

17. The combination and arrangement of elements as recited in claim 16, characterized further by adjustable means for regulating said control means selectively, so as to condition the control means for response to greater or lesser angular movement of said punch element incident to relative movement of the punching device and the material in work, while the punch element is in engagement with the work piece.

ROBERT H. E. SCHLECHT.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date Re. 10,193 DInfreville Sept. 5, 1882 175,189 Spencer Mar. 21, 1876 1,753,354 Weyandt Apr. 8, 1930 1,869,648 Ashworth Aug. 2, 1932 1,884,668 Gury Oct. 25, 1932 1,913,617 Smith June 13, 1933 2,077,937 Komow Apr. 20, 1937 2,193,878 Martln Mar, 19, 1940 2,286,022 Starck June 9, 1942 2,287,882 Huff June 30, 1942 2,418,762 Dehn et al. Apr. 8, 1947 2,432,176 Schubring Dec. 9, 1947 

